Cold start problems

[ChillyNoMore]

Here's my story. It's about 40 degrees and raining off and on today. About 1:30pm I went to fire up my Scan stove. Put in three medium sized pieces of dry Doug Fir, a bunch of kindling, and a few paper knots. The fire started nicely enough and the flue pipe temp went up to about 300 degrees in no time. So far, so good.

But then the flue temp started dropping and now I just have smoking, smoldering wood. I have opened the secondary air to try to get the fire going but that hasn't worked. I can't open the door to add another batch of kindling because I will end up with a room full of smoke. I have tried closing the primary and secondary air to get the smoking to stop but that hasn't worked either. So I can't start or stop this smoldering mess -- I'm in fire-building purgatory!

I typically find the first load of the day struggles, but then when I reload, the fire really takes off nicely and I have no more problems until the next cold start. Today, however, is a new low in my fire-building skills. :red: So how do I keep this from happening in the first place? And if it does happen, how do I fix it (short of waiting until the next day to try again)?

Thanks, as always, for sharing your wisdom!

ChillyRightNow

 

[EatenByLimestone]

When you start your fire, how do you have your primary air set? You mentioned opening the secondary, I think you meant primary, after the fire started to die down.

Did you notice any hissing from the wood?

It's only 40 outside, open some windows and get that smoldering wood outside!

Matt

 

[sandie]

IS it wet wood???? did you check the moisture of the wood with a meter? I start a fire and get it real hot before I had my medium sized wood, Kindling, paperknots and rounds that are about 3 inches or less across and let her rip to 650 degrees or maybe 700 degrees and then let her burn til it goes back to about 450 and then add my big wood which brings it to 650 again and then I shut my damper(it is either open or closed) and with the VC Resolute there is a "thermostat" that is a flap that you open when building the fire and when you are ready you put it where you want it and as it cools it opens up the flap to keep the heat as even as possible but DRY wood is a must.

 

[Backwoods Savage]

It sounds like the flue is simply not hot enough. The temperature rose to 300, but that was close to the stove. Probably further up the chimney it was so cold that it simply stopped everything. Simple answer is to get that flue hot and there are several ways to do this. One of the simplest and easiest is to burn papers....several of them. Lots of them even. Some people have used hair driers and torches to preheat the chimney before lighting a fire and it works. We've always just used papers if we had this problem. We just separate the pages and wad them up, throw them in the stove.....lots of them and then light it. When that gets burned down you can add a bit more plus kindling. In those conditions I like to use lots of kindling before adding any splits. I hope this helps. Good luck.

 

[Battenkiller]

12 feet from floor to cap—will it be enough??

Maybe not.

Sounds draft related to me. Once the fire is going strong, you get enough draft because the flue temps stay up. As soon as the fire starts to die back, the flue temps drop and the draft slows down.

I get a great draft in my outdoor Chimnea with only 3' of chimney, but today's stoves usually have a lot of internal resistance and require about 16' (give or take a foot or so) of chimney height to get enough draft to pull that air into the stove and through all the burn passages. Chimney height and flue gas temp both work together to feed air to the system. If one is lacking, the other must be in excess in order to get adequate air flow to the fire.

 

[ChillyNoMore]

I don't know how the Scan 61 compares to other stoves, but it has two ways to control the air intake. There is a slider on the top front of the stove (which I call primary) that I leave full open until the flue temp reaches 400. Then there is the ash drawer which the instructions say to leave open for no more than 5 minutes when first starting a fire (to avoid overfiring). When I started my fire today I had the ash drawer open per the instructions and the primary air open all the way. I only tried re-opening the drawer when the fire fizzled out after the kindling burned out before the main splits got going properly. Since the flue never got to 400, I never had a chance to start dialing down the primary air.

I think my wood is dry enough (~16% MC) but perhaps I am not using enough kindling and paper. I have been putting in 3 knots of paper and a handful of kindling. The stove has a quite small firebox so there isn't room for layers and layers of progressively smaller pieces (like tlingit's great technique shown here: http://www.woodheat.org/tips/topdownsteps.htm ) . Dennis, are you saying that you make a newspaper fire first and then a kindling fire before finally adding splits? If so, how do you avoid smoking yourself out?

One other (newbie) question: there is a damper control on the flue pipe which I have just left in the open position at all times. When in the burning cycle should I tinker with that control?

 

[begreen]

With a 128" of flue (10'8"), I was wondering if you would be posting about it. Add another 3 feet of pipe and I think it will start behaving itself.
https://www.hearth.com/econtent/index.php/forums/viewthread/49933/#553826

 

[ChillyNoMore]

Thanks for all the helpful comments. Sounds like it is time to invest in another hunk of pipe. I'm curious though why I only have this issue on my first fire of the day and never any problems with my subsequents loads of wood? Also, now that it is getting colder outside, shouldn't my draft be even better?

Sorry for all the questions but I am just trying to sort out all the different factors at play.